161257390 has 16 divisors (see below), whose sum is σ = 331729632. Its totient is φ = 55288224.

The previous prime is 161257379. The next prime is 161257391. The reversal of 161257390 is 93752161.

It is a super-2 number, since 2×161257390² = 52007891659224200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161257391) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1151769 + ... + 1151908.

It is an arithmetic number, because the mean of its divisors is an integer number (20733102).

Almost surely, 2^161257390 is an apocalyptic number.

161257390 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

161257390 is an abundant number, since it is smaller than the sum of its proper divisors (170472242).

161257390 is a wasteful number, since it uses less digits than its factorization.

161257390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2303691.

The product of its (nonzero) digits is 11340, while the sum is 34.

The square root of 161257390 is about 12698.7160768323. The cubic root of 161257390 is about 544.3019314931.

The spelling of 161257390 in words is "one hundred sixty-one million, two hundred fifty-seven thousand, three hundred ninety".